Essays about: "kromit"

Showing result 1 - 5 of 7 essays containing the word kromit.

  1. 1. Cr-spinels in the Franklinian Mobile Belt : a geochemical record of Paleozoic tectonics

    University essay from Stockholms universitet/Institutionen för geologiska vetenskaper

    Author : Malvina Forbes Halldén; [2019]
    Keywords : geology; geochemistry; spinel; Cr-spinel; chromite; SEM; scanning electron microscope; electron microprobe; EMP; electron probe microanalyzer; EPMA; electron micro probe analyzer; EMPA; petrogenetic indicator; microscopy; alteration; Franklinian Mobile Belt; Kulutingwak Formation; Clements Markham fold belt; Pearya; Paleozoic; suprasubduction zone; SSZ; island arc; IA; Arctic Canadian Archipelago; Ellesmere Island; Canada; 2017 Circum-Arctic Structural Events Expedition 19; Memorial University of Newfoundland; geologi; geokemi; spinell; Cr-spinell; kromit; SEM; svepeletronmikroskopi; elektronmikrosondanalys; EMP; EPMA; EMPA; petrogenetisk indikator; mikroskopi; Franklinian Mobile Belt; Kulutingwak-formationen; Clements Markham fold belt; Pearya; Paleozoikum; suprasubduktionszon; SSZ; öbåge; IA; Kanadas arktiska öar; Ellesmereön; Kanada; 2017 Circum-Arctic Structural Events Expedition 19; Memorial University of Newfoundland;

    Abstract : The chemical compositions of Cr-spinel extracted from mafic and ultramafic rocks collected on Ellesmere Island in the Arctic Canadian Archipelago were obtained through electron microprobe analyses. The extensively altered rocks are sampled from rock units in the Franklinian MobileBelt, which is representative of a Paleozoic tectonically active oceanic regime of which little is presently known. READ MORE

  3. 2. Chrome spinel grains from the Komstad Limestone Formation, Killeröd, southern Sweden : a high-resolution study of an increased meteorite flux in the Middle Ordovician

    University essay from Lunds universitet/Geologiska institutionen

    Author : Ellinor Martin; [2014]
    Keywords : chrome spinel; fossil meteorites; Komstad Limestone; winonaites; Middle Ordovician; carbonate sedimentology; Earth and Environmental Sciences;

    Abstract : I mellersta ordovicium var inflödet av kosmiskt material till jorden högre än idag, i sviter-na efter uppbrytningen av den L-kondritiska asteroidkroppen i asteroidbältet mellan Mars och Jupiter, vilket beri-kade den forna havsbottnen med meteoriter och kosmiskt damm. Komstadformationen i Killeröd, Skåne, innehåller ett lager särskilt rikt på L-kondritiska kromitkorn vilket indikerar en hög grad av kondensation. READ MORE

  4. 3. Cosmic ray tracks in chondritic material with focus on silicate mineral inclusions in chromite

    University essay from Lunds universitet/Geologiska institutionen

    Author : My Riebe; [2012]
    Keywords : extraterrestrial chromite; cosmic rays; cosmic ray tracks; ordinary chondrites; Ordovician; kosmisk strålning; spår efter kosmisk strålning; extraterrestrisk kromit; ordinära kondriter; ordovicium; Earth and Environmental Sciences;

    Abstract : It has been suggested that the cosmic ray flux varies as Earth moves relative to the spiral arms in the galaxy. However, no satisfying record over the cosmic ray flux over long time scales has been presented. READ MORE

  5. 4. A Russian record of a Middle Ordovician shower : extraterrestrial chromite in Volkhovian-Kundan (lower Darriwilian) strata at Lynna River, St. Petersburg Region

    University essay from Lunds universitet/Geologiska institutionen

    Author : Anders Lindskog; [2011]
    Keywords : Lynna River; extraterrestrial chromite; fossil meteorites; Volkhov; Kunda; Darriwilian; heavy minerals; Lenodus variabilis; Lynna; utomjordisk kromit; fossila meteoriter; tungmineral; Earth and Environmental Sciences;

    Abstract : Numerous fossil meteorites and high concentrations of sediment-dispersed extraterrestrial chromite (EC) grains with typical ordinary chondritic composition have previously been documented from 467±1.6 Ma Ma lower Kundan (Middle Ordovician) strata. READ MORE

  6. 5. Chromite in serpentine mud volcanoes of the Mariana forearc: Implications for abiotic organic reactions

    University essay from Institutionen för geologiska vetenskaper

    Author : Iga Sagatowska; [2010]
    Keywords : ;

    Abstract : The Mariana convergent plate margin is a non- accretionary subduction system in the western Pacific Ocean. Subduction of the Pacific plate causes dissolution of carbonate minerals releasing inorganic carbon, and causes dehydration of hydrous minerals in the subducted slab, generating hydrous fluids. READ MORE